Infectious diseases are the major cause of morbidity and mortality worldwide. Although infectious disease agents cause acute disease, many cause both acute and chronic infections. Persistent and latent infections that lead to active disease can be especially difficult to control, particularly because a reservoir of infection exists in the population. In general, these are the most difficult infections to treat, prevent and eradicate. Persistent or latent infections are caused by the spectrum of microbial agents, including viruses, bacteria, parasites, worms and fungi. Diseases caused by persisting pathogens include tuberculosis, schistosomiasis, AIDS, and a variety of herpes-related diseases. Exciting current research: - Common host immune mechanisms interface with a variety of microbes.-Immune modulation and evasion strategies still expanding in scope. - Immune response does not equal clearance; protective immunity still being defined. Problems in the field: - How to effectively enhance an, immune response to eliminate an organism that has evolved to be persistent in the host. - How to integrate information about the immune response to acute disease in the context of chronic and latent infections. - How to categorize-the persistent or latent state of a pathogen, and determine the genetic components that contribute to latency. - Bring together scientists from different fields to think about the concepts of latency and persistence, and share ideas from different fields. Goals: - Understand common themes in latent microbial infections, regardless of whether a virus, bacterium, parasite, worm, or fungus. - Contrast differences in immunologic memory during acute, chronic and latent infection (important in design of vaccine or treatment strategies). - Understand common immune mechanisms controlling latent or persistent microbes. - Identify stragies by which pathogens escape detection or elimination by the immune system, and design strategies to circumvent these pathogens (vaccine or drug development).